Dual film camera



-March 27, 1951 J. F. @RUBEN DUAL FILM CAMERA 2 Sheets-Sheet 2 Filed March 30, 1948 IN1r 'EN TOR. dames F @pube/7,

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Patented Mar. 27, 1951 UNITED STATES PATENT GFFICE DUAL FILM CAMERA .l ames F. Gruben, Roby, Tex.

Application March 30, 1948, Serial No. 17,990

2 Claims.

This invention relates to cameras having in.- terchangeable lmst An object of the invention is the provision of a camera in which two rolls of films are so mounted in the camera that a frame of either iilm may be exposed successively, one film being employed for drawing an unexposed frame of the other film into an operative position in line with the usual lens, the iilm which is in an inoperative position being protected rom light rays entering the camera.

A further object of the invention is the provision of a camera in which two rolls of films of different characteristics are so mounted in a camera that the films may be employed interohangeably, with a pair of spools for each lm, one of the spools of a pair accommodating the unexposed portion of the nlm, the other spool carrying the exposed portion of said film, each film providing a loop to receive a connecting means therebetween so that when the iirst-menu tioned spool of a pair is reversely rotated the associated loop will be fore-shortened for drawing an unexposed frame of the other lrn into` an operative position while withdrawing kthe other nlm into a sealed chamber, means being employed for retaining the second spool of a pair against rotation when the other spool is rotated reversely, the inactive iilm being protected from light rays.

The invention consists in the novel construction, arrangement and combinations of parts more particularly described and claimed.

In the drawings:

Figure 1 is a horizontal section through the center of my camera showing a frame of one lm in a position for exposure while the other film is housed and sealed against light rays,

Figure 2 is the same horizontal section shown in Figure 1 but disclosing the positions of the iilms in a reverse order,

Figure 3 is a transverse Vertical section of the camera taken along the line 3 3 of Figure l,

Figure 4 is a transverse vertical section of the camera taken along the line 4 4 of Figure 3,

Figure 5 is a fragmentary longitudinal vertical section taken along the line 5 5 of Figure l, and

Figure 6 is a plan view of a pair of rollers forming a connecting means between a pair of nlm and shown detached as a unit from the camera.

Referring more particularly to the drawings if! designates a casing having a reduced forward end il in which is mounted the lens barrel provided with a shutter and operating means there-1 for. vided with an opening i4 for exposing the frames of the films I5 and le has forwardly extended side walls Il. The outerends i8 of each side wall is curved laterally outwardly and secured to the adjacent side wall oi the housing I0 to form film chambers i5 and ISa.

A removable closure 2t for the rear open end of the camera casing itl includes a rear wall 2l, a top wall 22, a bottom wall 23 and end 'walls 24. The inner ends 25 of the end walls are curved as shown at 26 to fit neatly curved outer portions 2l of the casing. The top, bottom and end Walls of the closure iit snugly against the associated walls of the casing to prevent the passage of light to the interior of the camera. The inner end of the closure is open to permit light rays from the lens to pass directly to a film. A catch 28 maintains the closure in place.

A spring 3e is secured at 3i to the rear wall 2 of the closure 2S. The spring includes a pair of oppositely disposed curved arms 3E pressing against a presser plate, 33 which is guided in a frame @Il attached to the inner face of the wall 2i. The free ends of the spring are movable in openings 35 in the sides of the frame and causes the plate 331:0 exert a slight pressure on the' film for retaining said film in the focal plane. The opposite side edges of the plate are cut-away or beveled at 36 and 36a for a purpose which will be explained presently. The inner face of the presser plate aligns with the opening I4 which is at the focal plane in the partition wall I3.

A supply spool has the usual elongated slot to receive the inner end of the nlm I5 which has its unexposed portion trained on the spool Il?? While the remaining or exposed portion is trained on take-up spool or roller 43. The end 4l of the film is secured in the usual slot in the spool it. A manipulating knob 44 has a stem 45 re'- ceived by a passage 45 in a top wall 4T of the casing il) and by a larger passage i3 in the top wall 22 of the closure 29. The inner end 49 of the stein is flattened in the usual manner to receive a slot in the adjacent end of the spool lill. The take-up spool 43 is manipulated by a knob @so and has a stein 45a and similar parts for rotating said spool. Both knobs and the similarly arranged parts may be drawn outwardly for releasing the closure 2t! when the flattened portions @|9- of the stems are received by the openings 4l.

The other end of the spool 43 has a pawl 50 A partition having e, iiat rear wall i3 prou Y (Figure which is adapted to move over the teeth of a ratchet wheel 5i iiXed tc the wall 23 of the closure when 'the spool is revolved in the direction indicated by the arrow in Figure l. However, the teeth will prevent reverse rotation 5 of the spool. The ratchet wheel has a bearing (Figure 4) for the adjacent end oi the spool The other end of the spool d opposite from the knob da is received by a bearing 53 formed in the wall 23 of the closure 2Q. rlhe spool 15 may revolve in either direction.

D exposed portion of the nlm is inou-ed t rotation in opposite directions in the ida and is adapted to be revolved by a A knob 53a is adapted to revolve a taleor roller 5l carrying the exposed portici iilm i6. The upper' ends of the s' 5l are engaged by at portions of the stems attached to the r 55 and in a manner identica described in connect-ion with th i on the respective knobs ll and other end of spool si i bearing in a ratchet wheel the wall 23 of the closure A knob ends

of said spool in the direction indi arrow in Figure 2 but raven-ts .4, rota or" the spool. The outer or other end of the spool 55 revolves in a bearing E 3 formed in the wall of the closure 22. The spool t5 may be revolved in either direction.

A roller assembly shown in Figures l, 2 and 6 plays an important part in changing from film i5 to the nlm l and vice versa. The assembly is virtually a floating roller assem ily and includes a pair of parallel rollers and il@ joined at the ends by parallel bars 13's' the ends of the rollers are provided with pin 5B forming axles to permit rotation or the rollers. A baille mounted at its ends on intermediate porti ns of the bars and disposed midway between the rollers 55 and 66.

A slip loop of the nlm. i5 receives the roller G5 and is forme-d by sections of tL e nlm from the spools and A3. A slip loop li receives the roller S5 and is formed from sections ci the iilm i6 from the spools E5 and 5l.

Two types of lms may be employed in the camera. The roll i5 may contain a color iilni while ilm 55 may be of the black and white type. Two rolls of the black and white ty may be used having different speeds and revolving power. Whatever types o lms are selected, one roll as de is placed in the chamber i5 and the iree end thereof is looped around the roller then carried around the roll lo and inserted| into the elongated slot in the spool The film from the spool is threaded around the roller carried downwardly and around the roll of nlm iE on the spool 55. The free end of said lili is secured in the elongated slot in the si ool ie sensitive surface of the films must face the opening lf3.

A frame of the nlm is in an operative tion for photographic purposes. Before the ter in the camera has been actuated c desired to use the nlm l5 for the next the spool El is revolved in t ie direction indicated by the arrow in Figure l. Since spool 4S is held against reverse rotation the loop 'i8' will pull the roller assembly towards the chamber is until the assembly reaches the position shown in Figure 2.

The baille will be seated snugly between the meinber I3 and the beveled upper edge 36 of the presser plate 33 thereby excluding light from the chamber lil and the film therein. The spool 5l is retained against unwnding while the spool releases the unexposed portion of the film i@ which is drawn upwardly before the focal plane opening i4. in each case of a change in the lrns, one of the spools 45 and `55 is revolved to roll the unexposed lm thereon while drawing the unexposed portion oi the other nlm into an operative position.

This type of camera may be used with a focal plane shutter or between the lens type shutter. rlhis type o camera may incorporate the single lens reiiex feature.

If the frame o1 the film i5 before the opening i3 has been exposed the knob may be held stationary while the knob alla may be tur ed in the proper direction as indica ed by the arrow in Figure l. The exposed portion of said nlm will be wound on the spool while the roller as sembly is drawn to the chamber i9 by the loop l' as shown in Figure 2 with a frame or the iilm i5 being placed in position for the next exposure. The baffle will act to close the chamber i9 or the chamber lila to light rays to prevent the inoperative film from being exposed to iight rays.

What I claim:

l. In a camera comprising a casing provided with two nlm chambers spaced apart, an objective on the casing, and a transverse wall between the chambers having an opening therein substantially in the local plane of said objective, and there beingr a pressure plate spaced from the wall to Provide passage between the wall and the plate for movement of .Films therebetween, he improvement which includes a nlm supply spool disposed in cach chamber beyond the ends or^ said transverse wall, a take-up spool in each charnber disposed forwardly of the nlm supply spool therein and forwardly of the plane of said wall, means preventing reverse rotation and unwinding of each take-up spool, a baille movable between said wall and said pressure plate transversely of the optical axis of said objective, a pair or" bars forming roller supports spaced apart upon the baille, two slip loop rollers rotatably mounted between the roller supports on opposite sides of said baffle and accompanying he latter in its movement between said wall and said pressure plate, the pressure plate having the edges thereon beveled from the forward surface thereof, a frame secured in said casing with forwardly directed edges thereon lor removably retaining said pressure plate in predetermined position in which films from said supply spool are retained in a predetermined forwardly adjusted plane rearwardly of said transverse wall, two of said forwardly directed edges serving to limit movement o said baille and foniing limit stops therefor when the iilms on said supply spools are threaded over said slip loop` rollers at each side of the baille in such fashion as to form slip loops from which the lins r3xtend to the take-up rollers upon the same respective sides of the baille on which they connect with supply rollers, and iour manually operated knobs upon said casing with two knobs exteriorly ol' cach chamber thereof and individually connected to the supply and take-up rollers in said chambers.

2. In a. dual lm camera, a casing having a pair of spaced-apart film chambers arranged upon opposite sides of a lens, each chamber containing a film-supply roll and a lm-takeup roll,

a transverse wall arranged within the casing and extending between the lrn chambers and having an opening in substantial alignment with the lens, a presser plate spaced from said wall and forming' therewith a lm passage having oppo site ends leading into the film chambers and receiving lm from each oi said nlm-supply rolls, a connecting member arranged between the films adjacent the film passage and including a pair of spaced rollers about each of which a loop or" one lm formed between its supply and take-up rolls is adapted to be engaged, a baille plate interposed between the spaced rollers of said connecting member for alternately closing the opposite ends of the ilm passage, and knob means carried 15 2,426,628

REFERENCES CTED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,245,606 Rauch June 17, 1941 Stoiber May 13, 1947 

